The magnetic recording medium is a technique that utilizes the essential magnetic hysteresis feature of the recording medium to store and reproduce data. The basic bit “1” and “0” of a digital data are represented with different magnetized direction of the recording medium, so as to store these bit information.
The conventional recording schemes for storing information could be categorized into two types in accordance with the magnetic moment direction of the recording bit for the magnetic recording medium, which types are respectively a horizontal and a vertical recoding schemes. At present, the horizontal recording scheme is the most frequently used recording scheme. In the conventional horizontal recording scheme, the magnetic moment of recoding bit is laid on a surface of a thin film in parallel; however, once one would like to enhance the recording density of a magnetic medium and then tries to shrink the size of the recording bit, the demagnetizing field would thus be correspondingly increased, which causes the magnetic moment unstable. At the time, the written-in data become vulnerably vanished because of the bad thermal stability for the recording bit, which fails in meeting the requirement for the ultra highly recording density.
As to the aspect of the vertical recording scheme, the magnetic moment of recoding bit is perpendicular to a surface of a thin film. Once the size of the recording bit is shrunk, the recording particles will form a parallelepiped pillar architecture, so that the demagnetization field thereof becomes smaller whereby the unstable magnetic toque resulted from shrinking particles could be overcome, so as to completely preserve the recorded information. In particular, a granular perpendicular magnetic recoding medium possesses better thermal stability and recording resolution. As compared with the horizontal type recording medium, the granular perpendicular magnetic recoding medium could effectively promote the recording density for the recoding medium.
In order to reduce the magnetization transition jitter noise and to maintain enough medium signal to noise ratio (SNR) for the granular perpendicular magnetic recoding medium, in general, the magnetic recording particles are further shrunk to nano-scaled size. Nevertheless, such shrinkage will cause magnetic thermal instability for the granular perpendicular magnetic recoding medium system.
In order to overcome the mentioned drawbacks of the prior art, a perpendicular magnetic recording medium and method for fabricating the same are provided.